Radiology (Radiation Oncology)
- Junichi Hiratsuka, M.D., Ph.D. Professor
Main Areas and Themes of Research
High-dose-rate brachytherapy of prostate cancer: In Europe and North America, brachytherapy of the prostate using iodine-125 has been demonstrated as a promising treatment. Interstitial brachytherapy offers the clinician the advantage of introducing higher radiation doses to the prostate than those which can safely be delivered by conventional external radiotherapy. However, the implant technique of iodine-125 radioactive sources using TRUS guidance has inherent technical and radiobiological problems. A new brachytherapy modality using the high-dose-rate iridium-192 after-loading technique (HDR brachytherapy) has been applied to overcome the inhomogeneous dose distribution of interstitial seed brachytherapy. We adopted HDR brachytherapy as a boost of external beam radiotherapy and chose a single implant during one day with two HDR fractions.
Boron Neutron Capture Therapy (BNCT): BNCT makes it possible to destroy cancer cells selectively by high LET radiation (α-particle) without serious damage to the surrounding normal tissue. BNCT has been carried out for glioblastoma, malignant melanoma, and head and neck malignancies, and it has the potential to be one of the first-line cancer therapies in the near future. In this paper, we report the present situation and the future of BNCT.
Development of accelerated partial-breast irradiation (APBI) for breast-conserving patients: Early outcomes from studies evaluating APBI as an alternative adjuvant treatment after breast-conserving surgery for early-stage breast cancer have been promising. The method with the longest-standing history and supporting outcome data for APBI is multi-catheter interstitial brachytherapy. We have applied this therapy to APBI.
Although radiation therapy has long held a place among main cancer treatment modalities such as surgery and chemotherapy in Western countries, the situation was not the same in Japan. In Japan, radiation therapy was thought to be only a conservative and symptomatic treatment modality for cancers. But in recent years, many new promising modalities have been developed and good treatment results have been achieved, leading to an increase in the number of patients undergoing radiotherapy in large hospitals in urban areas. This trend is certainly related to Japan's rapid change into an aging society and tells us radiation therapy has been accepted as a less aggressive and function-preserving modality, especially for elderly cancer patients. New treatment modalities, such as remote after-loading brachytherapy with a micro-source, gamma-knives, cyber-knives and radio-surgery using linac, in combination with treatment-planning computers such as CT and MRI, are producing a high rate of function preservation and local control, which was not obtained by conventional treatment. Patient care, informed consent (IC) and quality of life (QOL) are indispensable for today's medical practice, and are also raised in importance in the field of treatment of malignant tumors.
Our department, which treats more than 700 cancer patients with radiotherapy per year, obtains IC on the basis of the offer of open information, performs medical practice supported by data from QOL analyses, and tries to maintain and improve the level of radiation therapy.
We want students to come in contact with current radiotherapy practice through lectures and bedside training, and to understand radiation physics and biology in relation to radiotherapy and treatment combined with other modalities such as chemotherapy and hyperthermia.
a) Block Lectures Regarding Neoplasms:
Cancer and apoptosis, radiation physics, radiation biology, clinical radiation oncology, combination therapy with chemotherapy or hyperthermia, and care of cancer patients (IC, QOL, terminal care, how to show respect for a patient's will).
b) Block Lectures Regarding Reproduction (Female):
Imaging of the female genital organ, radiation therapy for uterine cervical cancer and other gynecologic malignancies.
c) Bedside Training:
Treatment planning of radiotherapy for malignancies, assessment of treatment results, radiation protection.